Activation of monoamine oxidase type-B by aluminum in rat brain homogenate.

Monoamine oxidase type B (MAO-B) activity is elevated in certain neurological diseases such as Alzheimer's and Parkinson's disease with respect to age-matched controls; the cause of this elevation is unknown. The documented accumulation of aluminum in certain neurodegenerative diseases prompted us to test the effect of Al3+ on the activity of MAO-B in rat brain homogenate. Results showed that the metal ion significantly increased MAO-B enzymatic activity in a dose-dependent manner, yielding a K(M) of 5.69 microM compared with 34.45 microM in the absence of the metal ion. The Vmax of 45.34 micromol/min was unchanged in the presence of the metal ion.